package lt.marsrutai.mobile.android.util;

import java.util.Calendar;
import java.util.Comparator;

/**
 * Compares only hours and minutes of two Calendar instances
 *
 * @author Martynas
 */
public class CalendarHourMinuteComparator implements Comparator<Calendar> {

    public static final CalendarHourMinuteComparator INSTANCE = new CalendarHourMinuteComparator();

    @Override
    public int compare(Calendar cal1, Calendar cal2) {
        final int BEFORE = -1;
        final int EQUAL = 0;
        final int AFTER = 1;

        if (cal1 == cal2) {
            return EQUAL;
        }

        if (cal1.get(Calendar.HOUR_OF_DAY) < cal2.get(Calendar.HOUR_OF_DAY)) {
            return BEFORE;
        }
        else if (cal1.get(Calendar.HOUR_OF_DAY) > cal2.get(Calendar.HOUR_OF_DAY)) {
            return AFTER;
        }
        else if (cal1.get(Calendar.MINUTE) < cal2.get(Calendar.MINUTE)) {
            return BEFORE;
        }
        else if (cal1.get(Calendar.MINUTE) > cal2.get(Calendar.MINUTE)) {
            return AFTER;
        }
        else {
            return EQUAL;
        }
    }

}
